Process of purifying and refining hydrocarbon oils



March 31, 1636.

A. LAcHMAN PROCESS OF PURIFYING tND REFINING HYDROCARBON OILS Filed-July 26, 1929 2 Sheets-Sheet 1 .mi a

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INVENTOR BY #Pff/a@ iff/MM ATTORNEY March 31, 1936. A. I Acl-uvlAN`2,035,507

PROCESS OF PURIFYING' AND REFINING HYDROCRBON OILS 2 Sheets-Sheet 2 wwwA BNN. mmm

w y IIIIII A @N w .MM n mw Y m\..\\.\\\ K KMS mm m www@ ML fffcN wmmlmm@ wm (nur: mk wwu@ 9m mm Patented Mar. 3l, 1936 'rares ATi ortiesPROCESS OF PURIFYING AND REFINING HYDROCARBON OILS Application July 2,6,1929, Serial N0. 381,?05

19 Claims.

This invention relates to an improved process of purifying and refininghydrocarbon oils obtained by distillation or cracking of mineral oilssuch as lubricating oil stocks, lamp oil distillates, gasoline ornaphtha stocks, or distillates derived from shale oil, and morespecically refers to the treatment of gasoline or naphtha stock producedby cracking crude pretroleum oils or distillates derived from relativelyhigh sulphur bearing mineral oils, in which hydrogen sulphide,mercaptans and other sulphur bearing compounds, as well as varyingpercentages of oxygenated hydrocarbons and unstable hydrocarbons (suchas diolenes and acetylenes) may be present or formed during saiddistillation or cracking operation.

Reference is made to United States Patent No. 1,809,170, granted June 9,1931 to Arthur Lachman, Serial No. 361,513, led May 8, 1929 for Processof refining hydrocarbon oils, which discloses a vapor phase method orprocess for purifying and refining mineral oil products With a watersolution of certain metallic salts, or mixtures of the same, such aszinc, copper, cadmium, mercury iron, chromium, manganese,` aluminum,nickel or cobalt water soluble salts which may be the chloride, bromide,iodide, sulphate, sulphite, nitrate and also any of the water solublesalts of the above named metals of organic acids, such as the sulphonicacids of benzol, toluol and xylol, or the sulphonic acids derived fromthe treatment of petroleum oil with sulphuric acid, it being observedthat the enumerated metals may be classed as heavy metals and it beingunderstood further that the Word heavy as used in the term salt of aheavy metal (which latter phrase is embodied in the claims to comprehendthe materials capable of use in my process) is to be understood asincluding those metals which forni soluble salt solutions capable ofbeing maintained in solution at the temperatures and pressures at whichthe hereinbefore-described process may be practiced.

For the purpose of simplifying the description of my invention,reference will be made mainly to gasoline stock. Crude gasoline stocksobtained by distillation or cracking petroleum oils, consists of amixture of saturated and unsaturated hydrocarbons together with sulphurcompounds, nitrogen bases and other substances of an undened nature.These latter substances are readily oxidizable at ordinary temperatureand, are usually responsible for the change` of color which takes placeswhen refined gasoline is stored. These oxidizable substances are removedwith difficulty when gasoline stocksr are treated by the methods knownin the art.

By well-known methods, crude gasoline stocks obtained by distillation ofcrude petroleum oil or by cracking a higher boiling petroleum oil, arecustomarily treated with approximately from 1 per cent to as high as 8per cent or higher by weight, sulphuric acid, the quantity of sulphuricacid depending upon the nature of the gasoline stock to be treated andthe degree of relinement desired. This acid treatment usually consistsin commingling the gasoline stock with the required amount of sulphuricacid necessary to obtain the desired extraction, either by thewel1-known batch or continuous treatment, after which the products ofkthe acid reaction are permitted to settle and are then withdrawn fromthe treated gasoline stock. The acid treated gaso-` line stock is thenneutralized by washing with a water solution of an alkali and finallywith water. This treatment removes most of the impurities, butsubsequent treatments are usually necessary to deodorize and remove orconvert corrosive sulphur compounds into noncorrosive bodies. For thispurpose, a water solution of sodium plumbite or sodium hypochlorite isusually employed to render the gasoline stock sweet to the doctor test.In these treatments, particularly where hypochlorite of soda isemployed, chlorinated hydrocarbons may be formed to a small extent whichmay be converted into corrosive compounds during a subsequentdistillation.

The general objections to a treatment of this character, are as follows:(1) Gasoline purified by this method frequently becomes discolored whenstored for a period of time; (2) considerable quantities of sulphuricacid are required, which are diflicult to recover; (3) as high as 10 percent of the valuable unstable hydrocarbons contained in the gasoline.stock may be lost and (4) the treatment must frequently be followed by asweetening process, such as that heretofore described.

Now, I have discovered that the sulphuric acid normally used to treatcrude gasoline stocks may be reduced to a great extent, and in manycases may be entirely eliminated by the employment of a water solutionof certain metallic salts, or mixtures of the saine which may be zinc,copper, cadmium, mercury, iron,` chromium, manganese, aluminum,` nickelor cobalt water soluble salts, such as the chloride, bromide, iodide,sulphate, sulphite, nitrate, nitrite, and also any of' the water solublesalts of the above named metals of organic acids, such as the sulphonicacids of benzol, toluol and Xylol, or the sulphonic acid salts derivedfrom the treatment of petroleum oils with sulphuric acid.

The process described briefly consists in passing the hydrocarbon oilproduct, such as gasoline stock, in a liquid phase, commingled with asubstantially concentrated water solution of any of the above namedsalts or mixtures thereof, through a heating coil under a pressuresufficient to prevent any substantial vaporization therein, attemperatures of approximately 300 to 600 degrees F., and thenimmediately releasing the pressure and separating by distillation thepurified hydrocarbon oil pro-duct from the water solution of themetallic salt or salts, the extracted impurities and products ofpolymerization or condensation, or as shown in Figure II the gasolinestock and water solution of metallic salt or salts may be firstseparately heated and then commingled under a pressure.

The hydrocarbon oil stock to be treated by my invention may or may nothave had a preliminary treatment with sulphuric acid, or other agents topartlypurify the same, or may be first partly purified by my inventionand the purification completed by methods known in the art such astreatment with caustic alkali, sulphuric acid, etc. In the case ofgasoline stocks produced by cracking high sulphur bearing crudepetroleum oil or residuums, it may be advantageous to treat suchgasoline stocks with sulphuric acid or sulphuric anhydride at lowtemperatures, ranging from approximately 0 to 30 degrees F. before thetreatment with a concentrated water solution of any of the aforesaidWater soluble metallic salts at the elevated temperatures and pressuresheretofore stated and this treatment may also be followed by treatmentwith an alkaline water solution of sodium, potassium, or calciumhydroxide, or the carbonates of sodium or potassium.

Although a solution of less concentration may be employed which mayrange from 50 or less to approximately 85 per cent, the strength of theAwater solution of the metallic salt or mixtures of salts employed ispreferably a substantially concentrated solution, and the temperatureemployed for the treatment is preferably approximately 300 to 600degrees F.,-this Vtemperature depending upon the vaporizing temperature.of the oil under treatment.

One of the principal objects of this invention is to accomplish apurification of gasoline or naphtha stocks produced by thermo moleculardecomposition of high boiling petroleum oils, by a treatment with asubstantially concentrated water solution of a metal salt under apressure sufficient to prevent any substantial vaporization thereof andat a temperature of approximatelyV 300 to 600 degrees F., followed by adistillation and fractionation operation to separate the products ofreaction and higher boiling polymerized products from the purifiedgasoline or naphtha stocks.

Another object of the invention is to provide a continuous, rapid andeconomical process for purifying gasoline stocks produced by the thermodecomposition of higher boiling petroleum oils, by treating the sameunder super-atmospheric pressure sucient to maintain a liquid phase,with a substantially concentrated watersolution of a metallic salt attemperatures of approximately 300 to 600 degrees F., to polymerizesubstantially all the unstable hydrocarbons contained therein and at thesame time remove Various other objects and advantages of the presentinvention will be apparent from the description of the preferred form orexample of the process embodying the invention. For this purpose,reference is made to the accompanying drawings in which there isillustrated two forms of apparatus in which the invention may beperformed.

Figure I represents one form of an apparatus for carrying out theinvention in which the petroleum oil product to be treated is firstcommingled with the water solution of a metallic salt and thereafterheated to a reaction temperature by causing the same to pass through aheating coil under pressure.

Figure II represents another form of apparatus in which the petroleumoil product and the water solution of a metallic salt are separatelyheated to a reaction temperature and are thereafter commingled by meansof a jet mixer.

In- Figure I, 3 represents generally a tank for holding a supply ofgasoline or other petroleum oil stock to be processed. Pipe I,controlled by valve 2, connects the gasoline stock tank 3 near the topto a source of supply not shown. Pipe 4, controlled by valve 5, connectsthe gasoline stock tank 3 to the inlet side of pump 6. Pipe 4U,controlled by valve 4I connects pipe 4 to a fractionating tower notshown. Pipe I connects pump 6 to jet mixer 8. I3 represents generally atank for holding a concentrated water solution of a metallic salt suchas zinc chloride, zinc bromide, zinc iodide, etc., or any of the othermetal salts heretofore enumerated. Pipe I4, controlled by Valve I5,connects tank I3 near the top to a source of supply not shown. Pipe I I,controlled by valve I2, connects tank I3 near the bottom to the inletside of pump I. Pipe 9 connects the discharge side of pump I0 to jetmixer 8. Pipe |6 connects the jet mixer 8 to heater coil 38. The heatercoil 38 is stationed in the furnace I'I. 'I'he furnace is provided witha burner I8 which leads to a supply of fuel not shown. Pipe 39,controlled by pressure release valve I9, connects the heater coil 38 todistillation tower 20. The distillation tower 26 is provided with bubbletrays 2 I. Pipe 22, controlled by valve 23, connects the distillationtower 2! near the bottom to a source of water supply not shown. Pipe 25controlled by valve 24, connects distillation tower 23 at the bottom totank 26. Pipe 28 controlled by valve 21, connects the tank 26 to astorage not shown. The pipe 29 connects distillation tower 20 at the topto condenser coil 3|. Condenser coil 3| is stationed in the condenserbox 30 and is provided with a Water inlet pipe 32 and a water outletpipe 3'I. The pipe 32 leads to a source of water supply not shown andthe water outlet pipe 3l leads to a waste receiver not shown. Pipe 33connects condenser coil 3| to treated gasoline tank 34. Pipe 36,controlled by valve 35, connects the treated gasoline tank near thebottom to a storage not shown.

In Figure II, 3 represents generally a tank for holding a supply ofgasoline or other petroleum oil stock to be processed. Pipe I,controlled by valve 2, connects the gasoline stock tank 3 near the topto a source of supply not shown. Pipe 4, controlled by valve 5, connectsthe gasoline stock tank 3 to the inlet side of pump 6. Pipe 40,controlled by Valve 4I, connects pipe 4 to a fractionating tower notshown. Pipe 'I connects pump 6 to heater coil 38. Heater coil 33 isstationed in a furnace Il. Furnace I 'I is provided with a burner I8which leads to a fuel supply not shown. I3 represents generally a tankfor holding a concentrated water solution of a metallic salt such aszinc chloride, Zinc bromide, zinc iodide, etc., or any of the othermetallic salts heretofore enumerated. Pipe I ll, controlled by valve l5,connects tank i3 near the top to a source of supply not shown. Pipe IIcontrolled by valve I2, connects tank I3 near the bottom tothe inletside of pump Ill. Pipe 9 connects the discharge side of pump i Il toheater coil 44. Heater coil dll is stationed in furnace 42. Furnace 42is provided with a burner i3 which leads to a fuel supply not shown.Pipe 45 connects heater coil 44 to jet mixer 8. Pipe 39 connects heatercoil 38 to jet mixer 8. Pipe I 3 connects jet mixer 8 to reac-V tionchamber 4B. Pipe All controlled by pressure release valve IS, connectsreaction chamber 4E to distillation tower 2li. Distillation tower 2B isprovided with bubble trays 2I. Pipe 22, controlled by valve 23, connectsdistillation tower 2e to a source of water supply not shown. Pipe 25,controlled by valve 2d, connects the bottom of distillation tower 2! totank 2S. Pipe 2B, controlled by valve 2l, connects tank 26 to a storagenot shown. Pipe 29 connects distillation tower 28 at the top tocondenser coil 3 I. Condenser coil 3I is situated in the condenser box30, and is provided with a water inlet pipe 32 and a water outlet pipe3l. The pipe 32 leads to a source of water supply not shown and thewater outlet pipe 3l leads to a waste receiver not shown. Pipe 33connects the condenser box 3i) to treated gasoline tank 34. Pipe 38,controlled by valve 35, connects the treated gasoline tank 34 near thebottom to a storage no-t shown.

The process as carried out in the apparatus described in Figure I, is asfollows:

Tank 3 is lled with the petroleum oil product to be treated by operationof valve 2. Petroleum oil distillate, such as gasoline stock containedin tank 3, is permitted to ow through pipe Ll and into the inlet side ofpump 6, the rate of ilow being governed by operation of valve 5. Pump 6continuously discharges the gasoline stock under a pressure ofapproximately to 1000 pounds gauge, into jet mixer 8, wherein thegasoline stock is continuously commingled with the necessary quantity ofa substantially concentrated water solution of a metallic salt such aszinc chloride from the supply tank I 3.

The water solution of metallic salt contained in the supply tank I3 ispermitted to flow through pipe II and into the inlet side of pump I3which discharges the same under a pressure ranging from approximately100 to 1000 pounds gauge through pipe 9 and into said jet mixer 8, therate of flow being governed by operation of valve I2.

The quantity of water solution of metallic salt may range from as low asl per cent to as high as l0 per cent or higher, by volume, dependingupon the stock to be treated. For example, if a crude gasoline stockcontains a high percentage of impurities to be extracted as high as l0per cent by Volume or more of a concentrated water Ysolution of any ofthe aforesaid metallic salts or mixtures of the same may be employed.The pressure maintained on the system by means of pumps 3 and I e is soregulated that the commingled mixture of the water solution of metallicsalt or salts and gasoline stock under treatment passing through heatercoil 38 will be maintained in a substantially liquid phase, suchpressure depending upon the boiling point of the gasoline stock and thetemperature employed. From jet mixer 8, the gasoline stock, commingledwith the water solution of the metallic salt or salts passes throughheater coil 38, pipe 39 and pressure release valve IS, where thepressure is reduced to atmospheric or approximately atmospheric, andthen passes into distillation tower 23. The commingled mixture passingthrough heater coil 38 is heated to the reaction temperature. Preferablya temperature ranging from approximately 300 to 400 degrees F. issuitable to employ in treating ordinary gasoline stocks. However, withsome grades oi petroleum oil distillates, as high as ,600 degrees F. ora little higher, may be employed.

In distillation tower 2i), the puried gasoline stock at a temperatureranging from approximately 300 to 400 degrees F., together with aportion of the water content of the salt solution, are vapcrized andseparated from the products of the reaction and the metallic salt orsalts employed. The purified gasoline stock, mixed with "5' water vapor,passes out of distillation tower 23, through pipe 29, into condensercoil 3i, stationed in the condenser box 3e, wherein the said puriedgasoline stock and water vapor are condensed to a liquid, passingthrough pipe 33 and into the treated gasoline tank 311. A cooling fluidsuch as water is employed to condense the gasoline vapors passingthrough condenser coil 3l coming from a source not shown through pipe 32and passing out of condenser box 3e through i which separate in thebottom of distillation tower r;

253 are intermittently or continuously drawn into 35 through pipe 25,the ilow being controlled by valve 24, water being continuously orintermittently introduced into the lower section of dis tillation tower2li, through pipe 22, controlled by valve E3, in quantities sufficientto replace the vaporized water from the metallic salt water solution soas to maintain the used metallic salts or compounds and products of thereaction in a fluid condition.

From tank 26 the excess water solution of metallic salt or salts andproducts of the reaction are conducted to a storage not shown throughpipe controlled by valve 2l, and the metallic salts or compounds areseparated from the reaction products and purified for re-use.

As illustrated in Figures I and II, if it is desired to treat a gasolinestock coming directly from a fractionating tower, or other distillationapparatus, in a vapor or semi-vapor state, valve 5 is closed and valve@El is opened, which permits the gasoline stock coming from a source notshown, in a vapor or semi-vapor state, to flow through the pipe et] andinto the inlet side of pump 6, wherein the gasoline stock is completelycondensed to a liquid by the applied pressure maintained on the systemand the introduction of the cool water solution of a metallic salt orsalts in Figure I and by the application of pressure in Figure II.

The process as carried out in the apparatus described in Figure II issubstantially the same as the process heretofore described for Figure I,except that` the petroleum oil or gasoline stock to be treated and thewater solution of a metallic salt or salts are rst separately heated tothe reaction temperature by heating coils 38 and 44 at a pressuresufficient to prevent any substantial vaporization therein, after whichthe heated gasoline stools and heated water solution of a metallic saltor salts as heretofore enumerated are commingled in jet mixer 8 and passthrough pipe IG, reaction chamber 66, pipe 4T, pressure release valve land into distillation tower 2i).

While the process herein described is well adapted for carrying out theobjects of the present invention, it is to be understood that variousmodifications and changes may be made without departing from theinvention, such for example, as the use of centrifugal or othermechanical mixers, or the employment of any of the well-known contacttowers wherein a water solution of a metallic salt or mixtures ofmetallic salts, either organic or inorganic, heretofore enumerated, maybe commingled with or brought into contact with a petroleum oil at apressure sufcient to prevent substantial vaporization at the reactingtemperature, and the invention includes all such modications and changesas come within the scope of the appended claims.

What I claim is:

1. A process of purifying petroleum oil products, comprising,commingling a petroleum oil product with a substantially concentratedwater solution of a zinc salt, passing the commingled mixture through aheating coil and heating the mixture to a reaction temperature underpressure sufficient to prevent substantial vaporization, releasing thepressure and separating by vaporization, fractionation and condensationa purified petroleum oil product from products of reaction and excesstreating agent.

2. A process of purifying petroleum oil products, comprising,commingling a petroleum oil product with a substantially concentratedwater solution of a zinc salt, passing the commingled mixture through aheating coil and heating the mixture to a temperature of approximately300 to 60) degrees F. under pressure sufficient to prevent substantialvaporization, releasing the pressure and separating by Vaporization,fractionation and condensation a purified petroleum oil product fromproducts of reaction and excess treating agent.

3. A continuous process for purifying gasoline stocks, comprising,continuously commingling gasoline stock with a substantiallyconcentrated water solution of a Zinc salt, continuously passing thecommingled mixture through a heating element and heating the mixture toa temperature of approximately SUO to 600 degrees F., under a pressuresufhcient to prevent substantial vaporization, releasing the pressureand separating by vaporization, fractionation and condensation a puriedgasoline stock from products of reaction and excess treating agent.

4. A process of removing gum forming constituents from cracked gasolinestock, comprising, commingling a cracked gasoline stock with a watersolution of aV zinc salt and heating the commingled mixture to atemperature of approximately 300 to 600 degrees F., under a pressuresufficient to prevent substantial vaporization, while passing through a.heating'. coil, for a perod of time suicient to cause the unstablehydrocarbons contained in the cracked gasoline stock to polymerize withthe formation of gums, then reducing the pressure to approximatelyatmospheric and separating by vaporization, fractionation andcondensation a purified gasoline stock from products vof reaction,polymerization and excess treating agent.

5. A continuous process for purifying gasoline stocks derived bythermo-decomposition of higher boiling petroleum oils, comprising,continuously commingling gasoline stock with a water solution of zincsulphate, continuously passing the commingled mixture through a heatingcoil and heating the commingled gasoline stock and water solution ofZinc sulphate to a temperature of approximately 360 to 400 degrees F.,under a pressure sufficient to prevent substantial vaporization,continuously releasing the pressure after the commingled mixture ofgasoline stock and water solution vof zinc sulphate has passed throughsaid heating coil, continuously passing the treated gasoline stock,products of reaction and excess treating agent into a vaporizing tower,continuously vaporizing, fractionating and separating a purifiedgasoline stock and water vapor from' higher boiling reaction productsand excess treating agent.

6. A continuous process of purifying gasoline stocks derived by thethermo molecular decomposition of higher boiling petroleum oils,cornprising, continuously commingling gasoline stock with a watersolution of a zinc salt, continuously passing the commingled mixturethrough a heating coil and heating the commingled gasoline stock andVwater solution of zinc salt to a temperature of approximately 300 to400 degrees F., under a pressure suflicient to prevent substantialvaporization, continuously releasing the pressure and continuouslypassing the heated mixture of gasoline stock, water solution of zincsalt and products of reaction into a vaporizing tower, continuouslyVaporizing and separating by Vaporization, fractionation andcondensation a puried gasoline stock mixed with water from higherboiling products of reaction and excess treating agent, continuouslyintroducing water into the vaporizing tower in quantities suicient toreplace the water of vaporization, continuously withdrawing products ofreaction and introduced water containing excess treating agent,substantially as described.

7. A process of purifying gasoline stock, comprising, contactinggasoline stock with a water solution of a zinc salt while passingthrough a heating coil, under a pressure suicient to prevent anysubstantial vaporization, and heating the mixed gasoline stock and watersolution of Zinc salt to a temperature of approximately 300 to 400degrees F., releasing the pressure after the gasoline stock Inixed withthe water solution of Zinc salt has passed through the heating coil, andseparating by vaporization, fractionation and condensation a purifiedgasoline stock from higher boiling products of reaction and excesstreating agent.

8. A process of purifying petroleum oil, cornprising, commingling thepetroleum oil with a water solution of zinc salt, passing the commingledmixture through a heating coil and heating the commingled mixture to areaction temperature, under a pressure suicient to prevent substantialvaporization, releasing the pressure and passing the treated petroleumoil, products of reaction and water solution of Zinc salt into avaporizing tower, maintaining the zinc salt in a fluid condition byaddition of water, vaporizing, fractionating and separating a puriedpetroleum oil, mixed with water vapor, from higher boiling reactionproducts and excess treating agent.

9. A process of purifying petroleum oil products, comprising,commingling a petroleum oil product with a substantially concentratedWater solution of a zinc salt, passing the commingled mixture through aheating coil and heating the mixture to a temperature of approximately400 degrees F. under pressure sufcient to prevent substantialvaporization, releasing the pressure and separating by vaporization,fractionation and condensation a purified petroleum oil product fromproducts of reaction and excess treating agent.

10. A continuous process for purifying gasoline stocks, comprising,continuously commingling gasoline stock with a substantiallyconcentrated water solution of a zinc salt, continuously passing thecommingled mixture through a heating element and heating the mixture toa temperature of approximately 400 degrees F., under a pressuresufficient to prevent substantial vaporization, releasing the pressureand separating by vaporization, fractionation and condensation apurified gasoline stock from products of reaction and excess treatingagent.

11. A process of purifying gasoline stock, comprising, contactinggasoline stock with a Water solution of a zinc salt while passingthrough a heating coil, under a pressure suiiicient to prevent anysubstantial vaporization, and heating the mixed gasoline stock and watersolution of zinc salt to atemperature of approximately 400 degrees F.,releasing the pressure after the gasoline stock mixed with the watersolution of zinc salt has passed through the heating coil, andseparating by vaporization, fractionation and condensation a purifiedgasoline stock from higher boiling products of reaction and excesstreating agent.

12. A process of purifying petroleum oil products, comprising,commingling a petroleum oil product with a water solution of a salt of aheavy metal, passing the commingled mixture through a heating coil andheating the mixture to a reaction temperature under pressure sufcient toprevent substantial Vaporization, releasing the pressure and separatingby vaporization, fractionation and condensation a puried petroleum oilproduct from products of reaction and excess treating agent.

13. A process of purifying gasoline stock, comprising, contactinggasoline stock with a water solution of a salt of a heavy metal Whilepassing through a heating coil, under a pressure suflicient to preventany substantial vaporization, the gasoline sto-ck and Water solution ofthe metal salt being heated to a temperature of approximately 400 F.,releasing the pressure after the gasoline stock mixed with the watersolution has passed through the heating coil, and separating byvaporization, fractionation and condensation a puried gasoline stockfrom higher boiling products of reaction and excess treating agent.

14. A process of purifying a petroleum oil product comprising heatingsaid product and a substantially concentrated solution of the salt of aheavy metal under a pressure suflicient to prevent substantialvaporization and at a reaction temperature and-after the same have beencommingled under said premura-reducing the pressure and separating byvaporization, fractionation and condensation a purified oil product fromproducts of reaction and the excess treating agent.

15. 'Ihe process of purifying petroleum oil products comprising passingthe oil through a heating zone and maintaining the oil under pressuresuicient to prevent substantial vaporization while heating the oil to atemperature somewhere between 300 to 600 F., forcing into the stream ofoil a substantially concentrated water solution of a heavy metal salt,maintaining pressure on the mixture of oil and Water solution of thesalt after they are mixed, reducing the pressure and passing the mixtureto a collecting Zone, and fractionating the purified oil.

16. A process of purifying a petroleum oil product which comprisescausing said product to vaporize from a heated commingled mixture of theproduct and a water solution of a zinc salt by reducing the pressure onsaid heated mixture.

17 A process of purifying a petroleum oil product which comprisescausing said product to vaporize from a heated commingled mixture of theproduct and a water solution of an iron salt by reducing the pressure onsaid heated mixture.

18. A process of purifying a petroleum oil product which comp-risescausing said product to vaporize from a heated commingled mixture of theproduct and a water solution of a cadmium salt by reducing the pressureon said heated mixture.

19. The method of purifying a hydrocarbon initially available in a vaporor semi-vapor phase which comprises condensing said hydrocarbon byimposition of pressure thereupon and by commingling a cool aqueoussolution of a salt of a heavy metal therewith, maintaining a pressurethereupon While the mixture is heated to prevent substantialvaporization thereof, and nally reducing the pressure to vaporize saidmixture.

ARTHUR LACHMAN.

